The dried rice seeds were irradiated with accelerated ,56,Fe,40,Ar ions beams, or ,60,Co γ-rays at various doses and the effects on seeding growth, as well as micronuclei and chromosome aberration induction were oberved. The results indicated that the seeding height reduction, frequency of micronucleated cells and frequency of chromosome aberrations all appeared to dose dependent for these three types of rediation. The RBE value for seeding height reduction, determined at fifty percent of hight inhibition level, was found to be about 6.3, 1.9 and 1 for ,56,Fe,40,Ar and ,60,Co γ-ray respectively. However, the RBE values for the frequency of micronucleated cells were about 11,4 and 1 for ,56,Fe,40,Ar particles, and ,60,Co γ-ray. It appeared that the effectiveness of high LET radiation in inducing biological effects at the first generation was higler than that of low LET radiation, especially in inducing the microruclei formation.